Studies Provide Fresh Insight into the Ancestry of Early Europeans

A hunting group in the Stone Age (Victor Vasnetsov/Wikimedia Commons)

Two recently released studies have shed new light on ancient Europeans.

Taking maternally-inherited mitochondrial DNA samples from bones and teeth of the skeletons of 364 people who lived about 5,000 years ago in what is now Central Europe, researchers in one study said that they were able to reconstruct the first detailed genetic history of modern-day Europeans.

The research that is allowing scientists to map the history of human migration is the result of a 7 – 8 year collaborative effort between the Australian Centre for Ancient DNA (ACAD), at the University of Adelaide, the Johannes Gutenberg University Mainz, the State Heritage Museum in Halle (Germany), and the National Geographic Society’s Genographic Project.

“This is the largest and most detailed genetic time series of Europe yet created, allowing us to establish a complete genetic chronology,” said the study’s joint-lead author Dr. Wolfgang Haak of ACAD. “Focusing on this small but highly important geographic region meant we could generate a gapless record, and directly observe genetic changes in ‘real-time’ from 7,500 to 3,500 years ago, from the earliest farmers to the early Bronze Age.”

The scientists said that their research revealed a pattern of genetic replacement in people who lived in central Europe over a period of several thousand years.  This indicates that some rather intricate changes went into producing today’s Europeans.

They also pointed out that noticeable changes in the genetic composition of those living in a region we now know as Germany was the result of at least four stages of migration and settlement of people who not only came from a long regarded path through the Near East, but also from Western and Eastern Europe.

“None of the dynamic changes we observed could have been inferred from modern-day genetic data alone, highlighting the potential power of combining ancient DNA studies with archaeology to reconstruct human evolutionary history,” said Haak.

Ancient Egyptian farmer plowing (Wikimedia Commons)

The other study that examined the migration and settlement of Europe was led by scientists from Johannes Gutenberg University Mainz in Germany and the University College London in Great Britain.

This team of researchers, who also studied DNA taken from ancient human bones, found that native European “hunter-gatherers” – those who got their food from wild game and plants – lived side by side with immigrant farmers for about 2,000 years and were able to maintain their individual lifestyle much longer than was previously thought.

“It is commonly assumed that the Central European hunter-gatherers disappeared soon after the arrival of farmers”, said Dr. Ruth Bollongino, lead author of the study. “But our study shows that the descendants of Mesolithic Europeans maintained their hunter-gatherer way of life and lived in parallel with the immigrant farmers, for at least 2,000 years. The hunter-gathering lifestyle thus only died out in Central Europe around 5,000 years ago, much later than previously thought.”

Historians have said that farming or agriculture originated about 10,000 to 12,000 years ago in an area of the Near East known as the “fertile crescent” of Mesopotamia which included parts of today’s Iran, Iraq, Turkey, Syria, Lebanon, and Israel.  Descendants of those first farmers brought agriculture to Europe about 7,500 years ago.

“Until around 7,500 years ago all central Europeans were hunter-gatherers,” said Professor Mark Thomas, professor of evolutionary genetics at the University College London, and a co-author of the study. “They were the descendants of the first wave of our species to arrive in Europe, around 45,000 years ago. They survived the last Ice Age and the warming that started around 10,000 years ago. And now it seems they also survived the initial wave of farmers spreading across Europe from the southeast of the continent.”

While previous archaeological research has provided evidence of some forms of interaction between the native hunter-gatherers and their neighboring immigrant farmers, not much was known about the scope and length of their dealings with each other.

The newly released study showed that the farmers and hunter-gatherers did stay close to each other in proximity, maintained contact for thousands of years and even buried their dead in the same cave.

Scientists conducting palaeogenetic research in the ultra-clean laboratory at Mainz University (Thomas Hartmann)

But the interaction between the two cultures apparently did have some limits.  The researcher’s investigation revealed that while hunter-gatherer women sometimes married into families in the farming communities, the opposite may not have been true since no genetic lines of farmer women have been found in hunter-gatherers.

“This pattern of marriage is known from many studies of human populations in the modern world,” explained Burger. “Farmer women regarded marrying into hunter-gatherer groups as social demotion.”

The scientists said that their study showed that individually neither the hunter-gatherers nor the farmers represent the common ancestry of today’s Europeans, but instead came from a mix of both populations.